Self-aligned contact and contact over active gate structures
Methods of forming and processing semiconductor devices which utilize a three-color process are described. Certain embodiments relate to the formation of self-aligned contacts for metal gate applications. More particularly, certain embodiments relate to the formation of self-aligned gate contacts utilizing the formation of self-aligned growth pillars. The pillars lead to taller gate heights and increased margins against shorting defects.
1. A method of manufacturing an electronic device, the method comprising:
providing a substrate having an active region with at least one gate stack formed thereon, the at least one gate stack having a first side and a second side and comprising a gate metal having a thickness in a range of about 0.5 nm to about 2000 nm, a source/drain on the substrate, and a sacrificial material on the source/drain;
forming pillars on the gate metal;
forming a spacer material on the first side and second side of the pillars;
removing the sacrificial material to form an opening to the source/drain;
depositing a metal in the opening to form a source/drain contact;
removing the pillars to form trenches; and
depositing a dielectric material through the trenches onto the gate metal.
2. The method of claim 1 , further comprising recessing the source/drain contact to form gaps between the pillars and depositing a second dielectric material into the gaps.
3. The method of claim 1 , further comprising, prior to depositing a metal, depositing a liner material in the trenches to form a contact liner around the source/drain contact.
4. The method of claim 1 , wherein a gate liner surrounds the gate metal.
5. The method of claim 1 , further comprising selectively growing a seed layer on the gate metal, wherein the pillars are formed on the seed layer.
6. The method of claim 4 , further comprising, prior to depositing the dielectric material, removing the gate liner and etching the spacer material.
7. The method of claim 1 , further comprising, prior to depositing the dielectric material, removing the spacer material.
8. The method of claim 6 , further comprising depositing a contact on the source/drain contact.